Printing
Analyse how ink waste arises
Ink is often wasted in printing because an excess is mixed for the
assigned job. The ink is usually then disposed of due to pressure
over lack of quality, lack of storage space and inadequate rework
systems. By pinpointing how the excess is made and why it is
disposed of it will help identify the waste stream on which
minimisation techniques could be focused.
Draw down can be a source of inaccuracy during colour
matching
Where colour computer systems appear not to work, start by checking
the draw down preparation. To make a good draw down you need
consistent substrate, consistent draw bars, clean drawbars and well
trained operators.
Ink bases can vary
Only when draw downs and colour measurement are found and proven to
be perfect is it worth checking the ink bases to ensure that these
are of constant shade and strength. Discuss the systems and
variability with your ink supplier. Most suppliers now provide
specialist assistance, often including on-site support.
Keep press conditions constant
Ink will perform consistently only under constant press conditions
and these should be recorded and repeated. Press condition and
maintenance can be critical in ensuring consistency.
Tray waste can be significant
Ink waste is often designed into the presses-especially when the
presses are running small batches. Just filling the system can
cause a large surplus of ink which may or may not be reused. Check
pipe diameters, tray sizes, and pumps and tank sizes to engineer
the potential waste out of the system.